1. Field
Example embodiments relate to an intersection navigation system for a hoist to prevent a mover of a hoist unit from falling when the hoist unit passes an intersection.
2. Description of the Related Art
“Hoists” generally refer to devices that lift and transport articles. Hoists are used for transportation of freight in, e.g., storehouses and railroad stations, or for assembly and disassembly of machines in factories. In addition, hoists are used for transfer of semiconductor materials.
In the case of a ceiling traveling type hoist, rails on which the hoist will move are mounted to the ceiling, and a mover of the hoist moves along the rails to transport an article.
The hoist includes the mover to move on the rails upon receiving drive force, and a gripper to lift the article.
To change a movement direction during forward movement on the rails, the hoist uses branch rails diverged from a progress direction thereof. Selecting whether the hoist will move in the progress direction or in the diverged direction may be realized by changing a position of a divergence wheel provided at an upper end of the mover of the hoist.
However, using only the branch rails may cause an extended movement path from a starting position to a target position, resulting in inefficient operation of the hoist. That is, changing the movement direction of the hoist using the branch rails may result in long distance movement of the hoist in a roundabout way.